phase rule


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Related to phase rule: Phase diagram

phase rule

phase rule

n
(Chemistry) the principle that in any system in equilibrium the number of degrees of freedom is equal to the number of components less the number of phases plus two. See also degree of freedom, component4
References in periodicals archive ?
One important precept is the Gibbs phase rule, which limits the number of phases present to at most k phases per sample point, in a system involving k elements.
Material is organized in 13 chapters addressing the concepts of internal energy, entropy, and temperature dependence of heat capacities--and the three Laws of Thermodynamics; homogeneous and heterogenous equilibria, fugacity, activity, and equilibrium constant; Effingham-Richardson diagrams; phase rule and phase relations, phase stability, and thermochemical diagrams; phase equilibrium and transformation in metals under high pressures; and thermodynamics of special systems, solutions, electrochemical cells, point defects in binary inorganic compounds, and surfaces and interfaces.
One way to describe the situation is the phase rule (p + f = n + 2); where p is the number of phases present, f is the number of degrees of freedom, and n is the number of components present).
His topics include ideal gas laws, the thermodynamics of simple systems, entropy and the second law, equilibrium, the phase rule, liquids and solids, coulometry and conductivity, early quantum theory, experimentally determining molecular structure, classical molecular modeling, and photochemistry and the theory of chemical reactions.
This second phase rule would cover an additional 1,384 miles.